Apparatus for continuously feeding cut tobacco into a cigarette-making machine



May 26, 1970 M, LABBE 3,514,159

APPARATUS FOR CONTINUOUSLY FEEDING cu'r TOBACCO INTO A CIGARETTE-MAKING MACHINE Filed Nov. 8. 1967 United States Patent 0 3,514,159 APPARATUS FOR CONTINUOUSLY FEEDING CUT TOBACCO INTO A CIGARETTE-MAKING MACHINE Francis Auguste Maurice Labbe, Neuilly-sur-Seine, France, assignor to Molins Machine Company Limited, London, England, a corporation of Great Britain Filed Nov. 8, 1967, Ser. No. 681,333 Claims priority, application Great Britain, Nov. 15, 1966,

51,081/ 66 Int. Cl. B65g 53/60 US. Cl. 302--59 10 Claims ABSTRACT OF THE DISCLOSURE In a pneumatic feeding apparatus for feeding tobacco, e. g. to a cigarette-making machine, tobacco moves through a separating chamber, in which air is drawn off, and the tobacco then moves through a channel in which it forms an airlock for the separating chamber. One wall of the channel is movable at controlled variable speeds, and means are provided to control the rate of supply to the channel according to the quantity therein.

This invention concerns an apparatus for continuously feeding pneumatically supplied cut tobacco to a cigarette making machine or the like.

Background of the invention It is basically known to supply cut tobacco to cigarette making machines pneumatically through tubes, the tobac' co being conveyed through a tube by means of air flowing through the tube. In known apparatus of this kind, the tobacco is usually delivered in separate quantities.

Summary of the invention According to the present invention there is provided apparatus for feeding tobacco, continuously pneumatically supplied, to a cigarette-making machine or the like, comprising means to cause air and tobacco to 'be continuously drawn into a separating chamber from which air is continuously drawn oif while the tobacco continues to move, e.g. along a curved wall of the separating chamber, and a channel extending from the separating chamber into which the tobacco moves and forms therein an airlock for the exit of the separating chamber. One side wall of the channel may be movable in the direction of feed through the channel, for example the said one wall may be an endless band, which may be driven by a variable speed drive. There may be provided at the exit of the channel a door or closure member which is spring-urged towards a closed position and can be retracted, e.g. by a solenoid, to an open position.

The rate of tobacco supply to the channel may be controlled by control means actuated in response to detector means to detect the length or height of the tobacco column in the channel, e.g. a photo-electric device located at a suitable position along the length of the channel.

The channel may comprise a stationary wall whose tobacco-engaging surface is smooth, while the tobaccoengaging surface of the movable wall (e.g. a continuous band) may be rough.

The cross-section of the channel may increase in the direction of movement of tobacco through the channel.

The closure member at the exit end of the channel may be a pivoted flap or a movable roller.

Detector-means may be provided to detect the quantity of tobacco delivered from the channel and to actuate means to control the variable-speed drive which drives the endless band, thus varying the rate of feed from the 3,514,159 Patented May 26, 1970 ice channel. For example if the tobacco is delivered from the channel to the hopper of a cigarette-making machine, detector-means such as a photo-electric device may be located in the hopper to detect the quantity of tobacco therein.

Brief description of the drawing Apparatus in accordance with the invention will now be described with reference to the accompanying drawing, which shows an apparatus according to the invention in cross-section transversely to the width of the hopper of a cigarette-making machine.

Description of the preferred embodiment Cut tobacco is supplied through a pipe 1, air being sucked through the pipe and carrying the tobacco with it. The pipe opens into a chute the cross-sectional width of which increases towards its exit, at the right-hand side in the drawing, to the width of the hopper of the cigarette making machine, While its cross-sectional height somewhat decreases, although this height could remain constant if desired. The chute 2 opens into a separating chamber 3, in which tobacco and the conveying air are separated from each other.

Transversely through the separating chamber extends a sieve drum 4, the axis of which extends parallel to the width of the hopper, i.e. parallel to the axes of the carded drums 13 and 14 in the hopper.

The inner space of the sieve drum 4 is connected to a suction fan not shown, so that the conveying air is sucked into and exhausted from the interior of the sieve drum. The cut tobacco entering into the separating chamber 3 from the pipe 1 through the chute 2 moves, due to its high speed (the air speed in the pipe being approximately 22 m./sec., and the tobacco speed being approximately 15 m./ sec.) along the outer wall of the separating chamber, and is deviated along the cylindrical portion 5 of this wall, while the air is drawn inwardly into sieve drum 4. This sieve drum 4 is preferably driven so that its circumferential surface moves oppositely to the direction of movement of the tobacco, that is, anti-clockwise in the drawing.

The tobacco separated from the air, when leaving the cylindrical wall portion 5 of the separating chamber 3, moves along the wall portion 6 into a channel 7, which extends between a stationary wall 8 and a Wall 8a formed by a conveyor band, the cross-sectional width of the channel being approximately equal to the width of the hopper of the cigarette making machine. The cross-sectional dimension at right angles to its width, however, is only about 3 cm. The inner surface of the wall 8 is smooth so that the tobacco can easily slide along it, while the surface 8a of the conveyor band facing the tobacco is rough in order to urge the tobacco in the channel downwardly along the channel. The conveyor band runs around two rollers 9 and 10, the latter of which is driven by means of a variable-speed gear 11. Therollers, and thus the conveyor band, rotate in the direction indicated by the arrows. In order to ensure that, when the apparatus commences working and before a sufiicient amount of tobacco is in the channel 7, air cannot be sucked upwardly through the channel into the sieve drum 4, at the lower end of the channel there is a door or closure member shown as a pivoted flap 15, which is pivotably mounted at 16 and is urged by a spring 17 against the tobacco. In order to permit the tobacco to leave the channel, the closure member can be lifted from the roller 10 by means of a solenoid 18.

When tobacco passes from the separating chamber into the channel 7, it is first retarded and stopped in this channel by the door 15, and subsequently entering tobacco is retarded by the tobacco already in the channel, and tobacco therefore builds up in the channel to form a column. This column then prevents air leaking upwardly through the channel into the sieve drum 4, which would weaken the conveying air stream. Adjacent the channel there is provided a photo-cell detector device 19, which when the tobacco column builds back beyond the level of the detector device actuates control means to diminish or interrupt the supply of tobacco through the pipe 1.

A further photo-electric detector device 20 is arranged to measure or detect the height of the tobacco accumulating on or between the rollers 13 and 14 in the cigarette machine hopper, and according to the quantity of this tobacco, controls the variable-speed gear 11 so that the band 8a runs faster or slower and thus feeds more or less tobacco from the lower end of the channel.

The tobacco which leaves the lower end of the channel falls down near the main carded drum 13 of the hopper of the cigarette making machine which cooperates with the refuser drum 14 to form a tobacco fleece or carpet which is taken off the drum at a suitable place by means of a picker roller (not shown) to form the tobacco stream.

Instead of a pivoted flap 15, the closure member at the exit of the channel could be a movably mounted roller spring-urged to close the channel and retractable by means of a solenoid.

By meansof the arrangement described, pneumaticallysupplied tobacco can be delivered continuously, for example to the carded drums in the hopper of a cigarettemaking machine, while the rate of delivery and also the rate of supply can be regulated, and at the same time the tobacco moving through the channel forms an airlock thereby reducing the risk of loss of suction in the pneumatic conveying system. The provision of an endless band forming one wall of the channel provides a continuous drive for the tobacco, while the provision of a channel of suitable length enables irregularities in the tobacco entering the channel to be evened out and substantially reduced. Further, the arrangement makes it possible for the tobacco to be delivered to the hopper in a wellloosened condition and with less risk of the tobacco forming lumps, or of separation of long and short tobacco particle, than in a construction in which the pneumatically supplied tobacco is collected and delivered in separate quantities to the hopper.

What I claim as my invention and desire to secure by Letters Patent is:

1. Apparatus for feeding tobacco, continuously pneumatically supplied, to a cigarette-making machine or the like, comprising means to cause air and tobacco to be continuously drawn into a separating chamber from which air is continuously drawn off while the tobacco continues to move along a curved wall of the separating chamber, and a channel extending from the separating chamber into which the tobacco moves and forms therein an airlock for the exit of the separating chamber, said channel having two substantially parallel walls, one of which is movable in the direction of feed through the channel.

2. Apparatus according to claim 1, wherein the said one wall is an endless band arranged to be driven by a variable speed drive.

3. Apparatus as claimed in claim 2, comprising detector-means to detect the quantity of tobacco delivered from the channel, and operable to actuate means to control the variable speed drive for the said endless band, thus varying the rate of feed from the channel.

4. Apparatus according to claim 1 wherein the channel comprises a stationary wall having a smooth tobaccoengaging surface, and the tobacco-engaging surface of the movable wall is rough.

5. Apparatus for feeding tobacco comprising a separating chamber having a curved wall, an inlet to said chamber for directing a mixture of air and tobacco tangent to said curved wall, a channel extending tangentially away from said curved wall opposite said inlet, an outlet spaced from said curved wall between said inlet and said channel, and means for directing said stream of air carrying cut tobacco through said inlet into said chamber projecting said air stream and tobacco toward and tangent to said curved wall at suflicient speed to cause said out tobacco to be propelled against and delivered along said curved wall into said channel and to cause said air stream to pass through said outlet whereby said cut tobacco is separated from said air stream, said channel being defined by substantially parallel wall members extending away from said curved wall opposite said inlet for receiving and accumulating said separated tobacco to form a tobacco column of substantially uniform cross-section at least one of said wall members being movable in the direction of tobacco feed through the channel, and means for detecting the length of the column of tobacco in said channel to control the rate of tobacco supply to the channel and to prevent said column completely filling said channel.

6. Apparatus according to claim 5, comprising a closure member at the exit of the channel, means urging the closure member towards a closed position, and means operable to retract the closure member to an open position.

7. Apparatus according to claim 6, wherein the said closure member is a pivoted flap.

8. Apparatus according to claim 5, wherein the detector means is a photo-electric device.

9. Apparatus as claimed in claim 5 wherein said means for directing said stream of air carrying cut tobacco through said inlet and to cause said air stream to pass through said outlet comprises suction means.

10. Apparatus as claimed in claim 5 further comprising a cylindrical sieve drum in said chamber and spaced from said curved wall, said drum being connected to said outlet whereby said air stream passes through said drum to said outlet.

References Cited UNITED STATES PATENTS 760,494 5/1904 Sory 30228 1,191,072 7/1916 Fessenden 30217 1,642,135 9/1927 Wilkinson et al. 30228 1,971,421 8/1934 Mackenzie 30259 2,011,133 8/1935 Yoss 302-49 3,326,609 6/1967 Auten et al. 302-28 2,474,205 6/ 1949 Welty 30259 FOREIGN PATENTS 1,178,363 9/ 1964 Germany.

ANDRES H. NIELSEN, Primary Examiner 

